Cleanup and addition of toInternalSampleArray

packages/squiggle-lang/__tests__/Reducer/Reducer_Dispatch/Reducer_Dispatch_BuiltIn_test.res

@@ -17,6 +17,10 @@ describe("builtin", () => {
   testEval("1-1", "Ok(0)")
   testEval("2>1", "Ok(true)")
   testEval("concat('a','b')", "Ok('ab')")
+  testEval(
+    "addOne(t)=t+1; toInternalSampleArray(mapSamples(fromSamples([1,2,3,4,5,6]), addOne))",
+    "Ok([2,3,4,5,6,7])",
+  )
 })
 
 describe("builtin exception", () => {

packages/squiggle-lang/src/rescript/Distributions/SampleSetDist/SampleSetDist.res

@@ -83,7 +83,7 @@ let sampleN = (t: t, n) => {
   }
 }
 
-let samplesMap = (~fn: (float) => result<float, Operation.Error.t>, t: t): result<
+let samplesMap = (~fn: float => result<float, Operation.Error.t>, t: t): result<
   t,
   Operation.Error.t,
 > => {

packages/squiggle-lang/src/rescript/Reducer/Reducer_Dispatch/Reducer_Dispatch_BuiltIn.res

@@ -103,12 +103,11 @@ let callInternal = (call: functionCall, environment, reducer: ExpressionT.reduce
     let fn = r =>
       switch Lambda.doLambdaCall(aLambdaValue, list{EvNumber(r)}, environment, reducer) {
       | Ok(EvNumber(f)) => Ok(f)
-      | _ => Error(Operation.NotYetImplemented)
+      | _ => Error(Operation.SampleMapNeedsNtoNFunction)
       }
-    let newDist = SampleSetDist.samplesMap(~fn, sampleSetDist)
-    switch newDist {
+    switch SampleSetDist.samplesMap(~fn, sampleSetDist) {
     | Ok(r) => Ok(EvDistribution(SampleSet(r)))
-    | Error(r) => Error(RETodo(""))
+    | Error(r) => Error(REOperationError(r))
     }
   }
 

packages/squiggle-lang/src/rescript/Reducer/Reducer_ErrorValue.res

@@ -4,6 +4,7 @@ type errorValue =
   | REArrayIndexNotFound(string, int)
   | REAssignmentExpected
   | REDistributionError(DistributionTypes.error)
+  | REOperationError(Operation.operationError)
   | REExpressionExpected
   | REFunctionExpected(string)
   | REJavaScriptExn(option<string>, option<string>) // Javascript Exception
@@ -29,6 +30,7 @@ let errorToString = err =>
   | REExpressionExpected => "Expression expected"
   | REFunctionExpected(msg) => `Function expected: ${msg}`
   | REDistributionError(err) => `Distribution Math Error: ${DistributionTypes.Error.toString(err)}`
+  | REOperationError(err) => `Math Error: ${Operation.Error.toString(err)}`
   | REJavaScriptExn(omsg, oname) => {
       let answer = "JS Exception:"
       let answer = switch oname {

packages/squiggle-lang/src/rescript/ReducerInterface/ReducerInterface_GenericDistribution.res

@@ -262,6 +262,8 @@ let dispatchToGenericOutput = (
     Helpers.toDistFn(ToSampleSet(Belt.Int.fromFloat(float)), dist, ~env)
   | ("toSampleSet", [EvDistribution(dist)]) =>
     Helpers.toDistFn(ToSampleSet(env.sampleCount), dist, ~env)
+  | ("toInternalSampleArray", [EvDistribution(SampleSet(dist))]) =>
+    Some(FloatArray(SampleSetDist.T.get(dist)))
   | ("fromSamples", [EvArray(inputArray)]) => {
       let _wrapInputErrors = x => SampleSetDist.NonNumericInput(x)
       let parsedArray = Helpers.parseNumberArray(inputArray)->E.R2.errMap(_wrapInputErrors)

packages/squiggle-lang/src/rescript/Utility/Operation.res

@@ -56,6 +56,7 @@ type operationError =
   | InfinityError
   | NegativeInfinityError
   | LogicallyInconsistentPathwayError
+  | SampleMapNeedsNtoNFunction
   | NotYetImplemented // should be removed when `klDivergence` for mixed and discrete is implemented.
 
 @genType
@@ -70,6 +71,7 @@ module Error = {
     | InfinityError => "Operation returned positive infinity"
     | NegativeInfinityError => "Operation returned negative infinity"
     | LogicallyInconsistentPathwayError => "This pathway should have been logically unreachable"
+    | SampleMapNeedsNtoNFunction => "SampleMap needs a function that converts a number to a number"
     | NotYetImplemented => "This pathway is not yet implemented"
     }
 }